Her unit was posted near the Republic border, and even though the two interstellar nations were nominally at peace, there were frequent raids across the border. During these raids, Isabelle was able to make a name for herself due to her handling of her 'Mech and her knack of seeing options that others missed.[1]

When the Capellan Crusades started, she was a junior staff member of Sang-jiang-junMarko Sinković, who was the mastermind behind the early success the CCAF obtained. Isabelle learned as much as she could from him and was able to obtain the rank of Sang-jiang-jun before the invasion of the Republic in 3134.